title: Immune response after systematic lymph node dissection in lung cancer surgery: changes of interleukin-6 level in serum, pleural lavage fluid, and lung supernatant in a dog model.
abstract: BACKGROUND
  Systematic nodal dissection (SND) is regarded as a core component of lung cancer surgery. However, there has been a concern on the increased morbidity associated with SND. This study was performed to investigate whether or not SND induces significant immune response.
  
  
  METHODS
  Sixteen dogs were divided into two groups; group 1 (n = 8) underwent thoracotomy only, and group 2 (n = 8) underwent SND after thoracotomy. We compared interleukin-6 (IL-6) levels in serum, pleural lavage fluid and lung supernatant at the time of thoracotomy (T0) and at 2 h(T1) after thoracotomy (group 1) or SND (group 2). Severity of inflammation and IL-6 expression in lung tissue were evaluated in a semi-quantitative manner.
  
  
  RESULTS
  The operative results were comparable. IL-6 was not detected in serum in either group. IL-6 in pleural lavage fluid marginally increased from 4.75 ± 3.74 pg/mL at T0 to 19.75 ± 8.67 pg/mL at T1 in group 1 (P = 0.112), and from 7.75 ± 5.35 pg/mL to 17.72 ± 8.58 pg/mL in group 2 (P = 0.068). IL-6 in lung supernatant increased from 0.36 ± 0.14 pg/mL/mg to 1.15 ± 0.17 pg/mL/mg in group 1 (P = 0.003), and from 0.25 ± 0.08 pg/mL/mg to 0.82 ± 0.17 pg/mL/mg in group 2 (P = 0.001). However, the degree of increase in IL-6 in pleural lavage fluid and lung supernatant were not different between two groups (P = 0.421 and P = 0.448). There was no difference in severity of inflammation and IL-6 expression between groups.
  
  
  CONCLUSIONS
  SND did not increase IL-6 in pleural lavage fluid and lung supernatant. This result suggests that SND could be routinely performed in lung cancer surgery without increasing the significant inflammatory response.
authors.affiliation: Department of Thoracic and Cardiovascular Surgery, Yonsei University, College of Medicine, 50 Yonsei-ro, Seodaemun-gu, Seoul 120-752, Republic of Korea. kdjcool@yuhs.ac.
authors.forename: Seong Yong
authors.initials: SY
authors.lastname: Park
authors.forename: Dae Joon
authors.initials: DJ
authors.lastname: Kim
authors.forename: Abdullah
authors.initials: A
authors.lastname: Aldohayan
authors.forename: Iftikhar
authors.initials: I
authors.lastname: Ahmed
authors.forename: Sufia
authors.initials: S
authors.lastname: Husain
authors.forename: Ammar
authors.initials: A
authors.lastname: Al Rikabi
authors.forename: Abdulazeem
authors.initials: A
authors.lastname: Aldawlatly
authors.forename: Omar
authors.initials: O
authors.lastname: Al Obied
authors.forename: Waseem
authors.initials: W
authors.lastname: Hajjar
authors.forename: Sami
authors.initials: S
authors.lastname: Al Nassar
mesh_terms: D000818:Animals; D015415:Biomarkers / Q000032:analysis*; D001992:Bronchoalveolar Lavage Fluid / Q000737:chemistry*; D004195:Disease Models, Animal; D004285:Dogs; D004797:Enzyme-Linked Immunosorbent Assay; D007124:Immunoenzyme Techniques; D007249:Inflammation / Q000175:diagnosis* / Q000276:immunology / Q000378:metabolism; D015850:Interleukin-6 / Q000097:blood*; D008175:Lung Neoplasms / Q000097:blood / Q000601:surgery*; D008197:Lymph Node Excision; D013908:Thoracotomy
chemical_list: D015415:Biomarkers; D015850:Interleukin-6